latihan pdo

<?php
$user='gunawan';
$pass='';
try {

    $con = new PDO('mysql:host=localhost;dbname=test', $user, $pass); /*buka koneksi*/
    $con->beginTransaction();
/*=====ADA DATA DI INPUT.. NANTI DIBATALKAN */
    $sql="insert into mytable(name) value('SALAH')";
    $res = $con->exec($sql);
    $insertOK= $res!=false ?$res:false;
    if($insertOK){
        echo "OK .. total perubahan ".$insertOK;
    }
    else{
        throw new PDOException('code:'.$con->errorCode().'|error:'.implode("<br/>",$con->errorInfo()));
    }
/*QUERY AWAL*/
    echo "<p>DATA AWAL SEBELUM ROLLBACK</p>";
    $sql = "select name from mytable";
    $res = $con->query($sql);
    if(!$res){
        throw new PDOException('code:'.$con->errorCode().'|error:'.implode("<br/>",$con->errorInfo()));
    }
    else{
        foreach ($res as $row) { /*query dan tampilkan*/
            print $row['name'] . "\t";
            print "<br/>";
        }
    }
/* ROLLBACK */
    $con->rollBack();
/*QUERY SETELAH ROLLBACK*/
    echo "<p>DATA SESUDAH ROLLBACK</p>";
    $sql = "select name from mytable";
    $res = $con->query($sql);
    if(!$res){
        throw new PDOException('code:'.$con->errorCode().'|error:'.implode("<br/>",$con->errorInfo()));
    }
    else{
        foreach ($res as $row) { /*query dan tampilkan*/
            print $row['name'] . "\t";
            print "<br/>";
        }
    }

    $sql="insert into mytable(name) value('satu'),('dua')";
    $res = $con->exec($sql);
    $insertOK= $res!=false ?$res:false;
    if($insertOK){
        echo "OK .. total perubahan ".$insertOK;
    }
    else{
        throw new PDOException('code:'.$con->errorCode().'|error:'.implode("<br/>",$con->errorInfo()));
    }
    $con = null; /*untuk close */



} catch (PDOException $e) {
    print "Error!: " . $e->getMessage() . "<br/>";
    die();
}